Prior art cantilever shafts having a pulley generally comprise an arm that is fixedly attached to a mounting surface. The arm is not moveable with respect to a belt or chain.
Representative of the art is U.S. Pat. No. 6,224,028 B1 (2001) to Tanaka et al. which discloses a cantilever shaft assembly for rotating member comprising a steel shaft and a core shaft made of synthetic resin. A sprocket is supported to the free end of the cantilever shaft assembly.
Tensioners are also known that comprise an arm connected to a coil spring. The spring imparts a force on the arm thereby causing a belt tension. Such tensioners impart a relatively low force on a belt and have a relatively large range of movement.
The prior art either comprises a cantilever arm which relies upon an arrangement wherein the spring imparts a belt load, or a fixedly mounted cantilever arm having no spring rate to impart a belt tension. Further, the prior art tensioners allow a relatively wide range of movement, thereby causing a range of belt tensions.
What is needed is a cantilever tensioner having a high load capability. What is needed is a cantilever tensioner having a cantilever arm with a small range of movement for maintaining a belt tension. What is needed is a cantilever tensioner having an elastomeric member embedded in the cantilever arm for modulating a cantilever arm movement. The present invention meets these needs.